Other than the standard purge everything and select the layers giving you problem and press the u key twice to reveal all modified properties to look for problems I don't have any suggestions. Do you have automatic backups turned on? Maybe check one of those.

I discovered that if I hide every visual layer (every single one) the audio plays fine. I did vary turning layers on and off to try and isolate a problem layer but I have to turn off every layer except the audio.

I started a new project again, imported audio and everything was fine.

I created a shape layer and brought in an .ai file...everything fine.

I created some keyframes on the footage....everything fine.

I precomposed those layers...everything fine

I brought in .mov file which was the last thing I imported to my current project and the audio started playing a second ahead.

I turned off vis of that file and all was fine.

I went back to my current project, turned off the vis of that file and the audio was still busted.

I deleted it....still busted

Started a new project again and brought in other .mov files....audio played fine.

From one of my older projects that played the audio a second ahead when i tested it, I imported every piece of footage associated

with that file and audio played fine.

It's very strange...in a new project the problem seems isolated to that one particular .mov file (which I created this morning).

But back in my current project the deletion of that file has no effect on correcting the audio.

Also when I open older projects (I've tested three so far) the audio is one second ahead (approx)

The only thing I have not tried is a render to see what thew audio does.

I've seen many times people advising against the use of .mp3s in AE but I have never seen any reason given other than "AE does not like them". I have been using them (mp3's) for almost a year and a half (around 130 completed projects) and never had a problem. The reason I use them is because often when saving my edits as .wav or .aiff I would get glitches in the resulting files. Mp3s were the only file type that consistently gave me flawless audio.

The "raw" audio files I receive from my client vary. They are sometimes .wav, sometimes .aiff & sometimes .mp3. After i edit them I always render tham as .mp3 for the reasons stated above. Also if you read through the trouble shooting I did you will see the problem was very weird and didn't seem to have any logic to it.

There is no rhyme or reason to it but AE sometimes gets flaky dealing with compressed audio, It's no big deal to open an mp3 in Audition and export an uncompressed wav or aiff. Why, I bet Adobe Media Encoder could even do batches of them; haven't tried it, so I don't know.

Consider the conversion of compressed audio like carrying an umbrella on a cloudy day. It may be a little inconvenient to carry it, but you'd regret not having one if the skies open up.

I never use MP3 in production. Decoding the audio is just too unreliable. You do not add quality to the original audio but you do get more reliable deciding and if you need to manipulate the audio you have more bits and samples to work with.